Concrete slab with improved fastening means

ABSTRACT

A concrete slab having a number of peripheral recesses and fastening means disposed in each recess, respectively. In one embodiment, the fastening means includes an angle member having one portion secured to the slab and a second portion with holes therethrough for receiving mounting studs. A connector plate is provided to interconnect the studs passing through the angle members of adjacent slabs. In a second embodiment, the fastening means includes an angle member rigidly secured to the slab and having an angle element rigidly secured thereto to define a space for receiving a bolt. The slab is adapted for use in a number of different building applications and is particularly suitable for use in forming the floor of a building.

United States Patent 52/601 X 52/474 X 52/583 X 52/601 X wl. r. ..a lvm.t e W m n .ra n d w um w maw e m CT. Cabae ed SDASBmw 49680 33467 e99999 w S lllll n lll/l." 20974 m w l. O aT 07338 n 29326 Y 2,0,l15,7.We 98845 a m 47090 m0 9,l.4,.5, .n n.. 12233 PA [72] Inventor Marvin G.Nathtsheim Palo Alto, Calif.

[2l] Appl. No. 855,915

[22] Filed Sept.8, 1969 [45 l Patented Aug. 24, 1971 73 AssigneeNational Parking Corporation SanFranciscCalif.

[54] CONCRETE SLAB WITH IMPROVED FASTENING PATENTED m24 |971 SHEET 1 UF2 FIG.

Lc I Q E FI G. 3o

rNvrsN'rora MARVIN G NACHTSHEIM f/ ATTORNEYS BY W .MSOOBB SHEET 2 UF 2MM ATTORNEYS CONCRETE SLAB WITH IMPROVED FASTENING MEANS This inventionrelates to improvements in concrete slabs, and, more particularly, to aconcrete slab having improved fastening means on its outer periphery.

The present invention provides a building unit in the form of a precastconcrete slab which is capable of being used in any one of a number ofdifferent types of buildings. The slab is of the type which is adaptedto be secured by attachment or fastening means on its outer periphery toadjacent supporting framework so that a plurality of such slabs securedto the framework will form, for instance, a floor of a building. Thus,the slab of the invention is especially suitable for use in theconstruction of a multistored parking facility where the facility is tobe erected in minimum time and at minimum cost. These advantages can beachieved with the building slab of the present invention since thelatter has improved fastening means at each of a number of peripherallocations thereon so that, when the slab is moved into place on asupporting framework, it can be quickly and easily secured to theframework and thereby be rendered rigid. The slab is also constructed ina manner such that the same can be disassembled from its supportingframework when it is desired to move the building to another site or tostore the slabs and framework until further need for the same arises.

The fastening means on the slab of this invention can be made when theslab itself is molded. Thus, a large number of such slabs can be made atminimum cost and with the use of conventional forms. Also, the fasteningmeans is simple and rugged in construction and can be attached to thesupporting framework without the need for special tools and by workmenwho have no special skills.

The primary object of the present invention is to provide a concreteslab having improved fastening means on its outer periphery whichpermits the slab to be quickly and easily secured to an adjacentsupporting framework so that a plurality of such slabs can be used toform a building in minimum time and at minimum expense.

Another object of this invention is to provide a precast concrete slabwhose peripheral fastening means is simple and rugged in constructionand can be readily attached to adjacent supporting framework without theneed for special tools or special skills on the part of workmen usingthe slab to erect or disassemble a building.

A further object of the invention is to provide a building slab of thetype described which has peripheral recess means on one face thereof topresent a shoulder adjacent to the fastening means of the slab toprovide a guide for the positioning of the slab on a supportingframework to which the slab is to be attached to form a building.

Other objects of this invention will become apparent as the followingspecification progresses, reference being had to the accompanyingdrawings for illustrations of several embodiments of the slab.

ln the drawings:

FIG. I is a fragmentary top plan view of a building construe tionutilizing slabs made in accordance with this invention FIG. 2 is afragmentary, side elevational view of a multistoried buildingconstruction using slabs of this invention;

FIG. 3 is an enlarged, fragmentary perspective view of a pair ofadjacent slabs utilizing a first embodiment of the fastening means ofthis invention;

FIG. 3a is a top plan view of a portion of one side margin of the slabof FIG. 3;

FIG. 4 is a fragmentary cross-sectional view of the slab and fasteningmeans of FIG. 3;

FIG. 5 is a fragmentary, top plan view, partly broken away, of a secondembodiment of the fastening means of the invention;

FIG. 6 is a side elevational view, partly broken away, of the fasteningmeans of FIG. 5 and FIG. 7 is a cross-sectional view, partly brokenaway, of the fastening means of FIGS. 5 and 6.

The first embodiment of the building slab of this invention isillustrated in FIGS. 3 and 4 and is denoted by the numeral 10. The slabis precast and formed of concrete and has fastening means l2 at each ofa number of locations on its outer periphery.

Slab 10 can be utilized in any desired manner, but, for purposes ofillustration, it will be described as being usable with other, identicalslabs to form a building, such as a multistoried parking facility. Sucha building is comprised of a framework 14 (FIG. 2) and a plurality ofslabs l0 coupled to framework 14 and arranged in a generally horizontalplane at each story of the building to define a parking surfacetherefor. As shown in FIG. 1, a plurality of slabs 10 are arranged inside-by-side, end-to-end relationship to form the parking surface of aparticular story, the slabs 10 at each story being supported by a numberof horizontal beams 48 secured together and to a number of verticalcolumns 18, beams 48 and columns 18 forming parts of framework 14.Fastening means l2 of each slab 10 is used to attach the slab to arespective beam 16 so as to render the slab fixed relative to framework14. Slab l0 of this invention can be used in building applications otherthan that illustrated in FIGS. 1 and 2. A

As shown in FIGS. 1 and 3a, each slab l0 is provided with a number ofspaced, peripheral recesses 20 therein, there being a fastening means 12at each recess 20, respectively. For purposes of illustration, onerecess 20 is on each side of a slab and one recess 20 is at each end ofthe slab. The arrangement of the recesses could be different, ifdesired, FIG. 3a shows a top plan view of a portion of the slab lookingvdownwardly onto a recess 20 therein.

In each recess 20 of slab l0, there is provided an L-shaped connectormember 22 made of angle iron, rigidly secured to the slab, and forming apar of fastening means l2. Each member 22 has a pair of mutuallyperpendicular plate sections 24 and 26 which are integral with eachother. Plate section 24 is in abutment with a flat surface of slab 10forming the innermost extremity of recess 20. A pair of elongates studs28 are rigidly connected to plate section 24 and are embedded in theslab as shown in FIGS. 3 and 4. These studs hold member 22 rigidlysecured to the slab and within the corresponding recess 20.

The width of plate section 24 is substantially equal to the width of thecorresponding recess 20, as shown in FIG. 3a. Plate section 26 has anouter or bottom surface 30 which is substantially flush with the outeror bottom surface 32 of slab 10. Plate section 26 also has a pair ofspaced holes 34 and 36 therethrough (FIG. 3a hole 34 adapted to receivea threaded bolt 38 having a head 40 and hole 36 adapted to receive athreaded stud 42 extending upwardly from the upper surface 44 of thelateral portion 46 of a horizontally disposed I-beam 48 forming a partof a framework for supporting slab l0 in an operative position. Whilestud 42`is shown as being welded to upper surface 44 of I-beam 48, it isclear that the stud could comprise a bolt extending through an openingin the l-beam. The size of hole 36 is larger than the diameter of stud42, whereby member 22 can accommodate itself to stud 42 even thoughthere is an error in the position of the stud on the I-beam. Platesection 26 extends from plate section 24 to the entrance of thecorresponding recess, as shown in FIGS. 3a and 4.

In use, slab 10 is mounted on a framework having I-beam 48 as a partthereof (FIGS. 3 and 4) with the I-beam having a plurality of upright,threaded studs 42 thereon. To construct a floor of a parking facility,for instance, a plurality of slabs l0 are utilized, each pair ofadjacent slabs having mating recesses 20 in the manner shown in FIG. l.There is a pair of studs 42 secured to I-beam 48 adjacent to each pairof mating recesses, as shown in FIG. 3.

At each recess location, each stud 42 is received within a correspondinghole 36, whereby the corresponding `slab l0 is held against lateralmovement on the corresponding I-beam 48. To further secure the slab tothe l-beam, a connector plate 50 is provided, plate 50 having fourlongitudinally aligned holes therethrough, the two centrally disposedholes being provided to receive respective studs 42 and the two outerholes being provided to receive respective bolts 38. Nuts 52 arethreaded onto bolts 38 so as to clamp connector plate 50 to adjacentmembers 22. A washer 54 is generally provided between nut 52 and plate50. A nut 56 is threaded onto each stud 42, respectively, so as tofurther clamp connector plate 50 to members 22.

The foregoing connection structure is utilized at each of the matingpairs of recesses 20. In this way, a plurality of slabs are releasablysecured to respective I-beams 48 for support thereby.

When completely assembled, adjacent slabs 10 will be spaced slightlyapart so as to define a space 58 therebetween. This space is provided toallow expansion and contraction of the slabs due to temperaturevariations and can be filled with a suitable filler material, such as apolysulfide. Concrete grout is preferably used to fill mating recessesand thereby cover the fastening means in the recesses. These materialscan be removed from spaces 58 and recesses 20 when it is desired todisassemble the building to permit the slabs and the supportingframework to be moved to another location or to be stored until readyfor use again.

A second embodiment of the slab of this invention is illustrated inFIGS. 5-7 and is broadly denoted by the numeral 110. The slab hasfastening means 112 thereon at each of a number of locations on thesides and end portions thereof in the same manner as that describedabove with respect to slab 10.r For purposes of illustration only,fastening means corresponding to a single recess is illustrated. Such arecess is broadly denoted by a numeral 120, the latter having an innersurface 121, a bottom surface 123, and a pair of side surfaces 125.Bottom surface123 is spaced above the bottom surface 132 ofslab 110.` Y

An L-shaped member 122 is provided for each recess 120, respectively.Each member 122 is provided with an outer plate section 124 which issubstantially flush with the outer side surface 127 of slab 110. Member122 is further provided with a second plate section 126 which isintegral with and substantially perpendicular with plate section 124, asshown in FIG. 7. Plate section 126 is provided with a hole 134therethrough. An anglernember 129 has a pair of mutually perpendicularsides 131 and 133 which are integral with each other and are welded attheir outer end edges 135 to the inner surface of plate section 124, asshown in FIG. 5, so as to define with plate section 124 a space 137.This space is open-ended to receive a bolt 139 having a head 140, thebolt also being received within hole 134 in the manner shown in FIG. 7so that the bolt is used to couple slab 110 to an l-beam 148 having ahorizontal portion 146 through which bolt 139 also extends.

The outer surfaces of sides 131 and 133 of element 129 are in abutmentwith the concrete slab 1 10 and a pair of studs 128 rigid to platesection 124 are embedded in the concrete so as to hold member 122 in afixed position with respect to the slab. The upper end edges of sides131 and 133 are substantially flush with bottom surface 123 of recess120.

Slab 110 is utilized by placing the same on the horizontal portion 146of a corresponding l-beam 148. Slab 110 is made so that the bottomsurface of plate section 126 is spaced above the bottom surface 132 ofslab 110 so as to present an offset shoulder 141 for facilitating theplacement of the slab on the lbeam. ln this way, shoulder 141 serves asa stop to limit' the lateral movement of the slab across the top surfaceof horizontal portion 146 of the l-beam. Thus, there is no danger of thebeam being moved too far laterallyso as' to slip off the supportingsurface of the beam.

when the slab is in the proper location, bolt 139 is inserted throughhorizontal portion 146, into and through the space 137 so that the boltprojects upwardly from the bottom surface 123 of recess 120.Alternatively, bolt 139 can be secured to the l-beam to permit the slabto be lowered onto the l-beam with the bolt being received within space137. Hole 134 is y oversized to compensate for any error in theplacement of bolt 139. After the slab is in place, aconnector plate 143lisfreceived over the bolt and engages the upper end edges of secure theslab to the I-beam.

After the nut has been put on the bolt, the recess 1204can be` filledwith a concrete grout. The spaces between the side faces i of adjacentslabs l 10 can be filled with a plastic material, such as a polysulfideor the like. When this has been done, the building is complete and readyfor use. l

Slabs l0 or 1 10 can be elevated into position in any conventionalmanner. If a parking facility is constructed with the slabs, the lattercan be moved into position, one-by-one, and secured to the underlyingframework in the manner described above. ln this way, the facility canbe erected in a minimum of time yet be sufficiently rugged inconstruction to satisfy the requirements of building codes. Moreover,the facility can be disassembled and the slabs and framework moved toanother site or stored for subsequent use as a parking facility or asany other type of building. The slab of the present invention providesfor the foregoing advantages because its fastening means is simple inconstruction yet it can be quickly and easily connected and disconnectedfrom the adjacent framework without the need for special skills.

If a number of slabs 10 are used to form the floor of a building, theslabs at the ends and sides of the building will, for purposes ofillustration, abut adjacent side and end walls. ln such a case, onlyone-half of each connector plate 50 is required, the half-plates beingcoupled to respective bolts 38 and studs 42.

What is claimed is:

1. A building unit for attachment to a beam comprising: a concrete slabhaving a pair of opposed, generally flat faces and an outer peripheryprovided with a number of spaced recesses extending into the slab, saidslab adapted to be mounted in an operative position with one of saidfaces on said beam and with one of said recesses above the beam; andfastening means in each recess respectively, said means including anangle member having a first section rigidly secured to the slab and asecond section adjacent to the lower portion of the correspondingrecess, said second section being engageable with the beam and providedwith an opening therethrough for receiving an elongated fastening deviceextending upwardly from the beam, the portion of the recess above saidsection being sufficient to permit a fastener to be removably receivedwithin the recess and to be coupled to said fastening device, wherebythe slab can be coupled to a supporting framework by the device.

2. A building unit as set forth in claim 1, wherein the second sectionis substantially ilush with said one face.

3. A building unit as set forth in claim 1, wherein said second sectionis in a plane substantially parallel with and adjacent to the majorportion of said one face.

4. A building unit as set forth in claiin l, wherein the second sectionhas a second opening therethrough spaced from the first opening, andincluding a connector plate receivable in a recess and having a pair ofholes therethrough for alignment with respective openings whereby theconnector plate can interconnect the angle member and an adjacentframework.

5. A building unit as set forth in claim l, wherein each recess has aninner surface and a pair of opposed side surfaces, the first sectionbeing in abutment with said inner surface, the second section beingflush with said one face and in substantially spanning relationship tosaid side surfaces, the region of said recess between said secondsection and the other of said faces being open.

6. A building assembly comprising: a beam having a generally flatsurface and adapted to support a mounting stud extending outwardly fromsaid surface; a slab having a pair of opposed faces and an outerperiphery having a number of spaced recesses, the slab beingpositionable with one of said faces in engagement with the surface ofthe beam and with at least one of the recesses adjacent to said surface;and fastening means carried by the slab at each recess, respectively,for interconnecting the 'slab and the beam, said fastening meansincluding an angle member rigidly secured to the slab and having a lowerportion provided with an opening therethrough for receiving the mountingstud, said lower portion being flush with said one face of the slab endengageable with said surface of the beam and a connector platereceivable within the corresponding recess and having a hole forreceiving said stud, said plate being operable to clamp the angle memberto said beam when a nut is threaded onto the stud, said plate extendinglaterally from the adjacent extremity of said slab, whereby theconnector plate can be coupled to a second slab for clamping the latterto said beam.

7. A building assembly comprising: a beam having a generally flatsurface and a bolt-receiving opening therethrough; a building slabhaving a pair of opposed faces and an outer periphery having a number ofspaced recesses, the slab being positionable with one of said faces inengagement with the surface of the beam and with at least one recessadjacent to said surface; and fastening means carried by the slab ateach recess, respectively, for interconnecting the slab and the beam,said fastening means including an angle member having a first sectionrigidly secured to the slab and a second section integral with the firstsection and extending laterally therefrom, said second section beingdisposed substantially flush with said one face and having a holetherethrough alignable with said opening of the beam, an angle elementhaving a pair of opposed sides with each side having an outer marginaledge, the marginal edges of said sides being rigidly secured to saidfirst section, said sides defining a space aligned with said hole in thesecond section, each of said sides having a side marginal edge, and aplate spanning the side marginal edges of said sides for use in clampingsaid slab to the beam when a bolt extends through the opening, the holeand the space and when a nut is threaded onto the bolt.

8. A building unit comprising: a concrete slab having a pair of opposedfaces and an outer periphery provided with a number of spaced recessesextending into the slab; and fastening means in each recessrespectively, said means including an angle member having a firstsection rigidly secured to the slab and a second section provided withan opening therethrough for receiving a fastening device, and an angleelement having a pair of sides with each side having an outermostmarginal edge, the marginal edge of said sides being rigidly secured tothe first section to present a space between said sides and aligned withthe opening in the second section whereby the slab can be coupled to asupporting framework by the device, the second section being adjacent toone ofthe faces.

9. A building unit as set forth in claim 8, wherein each side of saidelement has an end marginal edge, and including a plate for spanningsaid end marginal edges and having a hole therethrough alignable withsaid space.

10. A building unit as set forth in claim 9, wherein the end marginaledges of said element are disposed between said opposed faces.

11. A building unit as set forth in claim 8, wherein said slab has aperipheral end face adjacent to each recess, respectively, the firstsection being substantially flush with said end face.

1. A building unit for attachment to a beam comprising: a concrete slabhaving a pair of opposed, generally flat faces and an outer peripheryprovided with a number of spaced recesses extending into the slab, saidslab adapted to be mounted in an operative position with one of saidfaces on said beam and with onE of said recesses above the beam; andfastening means in each recess respectively, said means including anangle member having a first section rigidly secured to the slab and asecond section adjacent to the lower portion of the correspondingrecess, said second section being engageable with the beam and providedwith an opening therethrough for receiving an elongated fastening deviceextending upwardly from the beam, the portion of the recess above saidsection being sufficient to permit a fastener to be removably receivedwithin the recess and to be coupled to said fastening device, wherebythe slab can be coupled to a supporting framework by the device.
 2. Abuilding unit as set forth in claim 1, wherein the second section issubstantially flush with said one face.
 3. A building unit as set forthin claim 1, wherein said second section is in a plane substantiallyparallel with and adjacent to the major portion of said one face.
 4. Abuilding unit as set forth in claim 1, wherein the second section has asecond opening therethrough spaced from the first opening, and includinga connector plate receivable in a recess and having a pair of holestherethrough for alignment with respective openings whereby theconnector plate can interconnect the angle member and an adjacentframework.
 5. A building unit as set forth in claim 1, wherein eachrecess has an inner surface and a pair of opposed side surfaces, thefirst section being in abutment with said inner surface, the secondsection being flush with said one face and in substantially spanningrelationship to said side surfaces, the region of said recess betweensaid second section and the other of said faces being open.
 6. Abuilding assembly comprising: a beam having a generally flat surface andadapted to support a mounting stud extending outwardly from saidsurface; a slab having a pair of opposed faces and an outer peripheryhaving a number of spaced recesses, the slab being positionable with oneof said faces in engagement with the surface of the beam and with atleast one of the recesses adjacent to said surface; and fastening meanscarried by the slab at each recess, respectively, for interconnectingthe slab and the beam, said fastening means including an angle memberrigidly secured to the slab and having a lower portion provided with anopening therethrough for receiving the mounting stud, said lower portionbeing flush with said one face of the slab end engageable with saidsurface of the beam and a connector plate receivable within thecorresponding recess and having a hole for receiving said stud, saidplate being operable to clamp the angle member to said beam when a nutis threaded onto the stud, said plate extending laterally from theadjacent extremity of said slab, whereby the connector plate can becoupled to a second slab for clamping the latter to said beam.
 7. Abuilding assembly comprising: a beam having a generally flat surface anda bolt-receiving opening therethrough; a building slab having a pair ofopposed faces and an outer periphery having a number of spaced recesses,the slab being positionable with one of said faces in engagement withthe surface of the beam and with at least one recess adjacent to saidsurface; and fastening means carried by the slab at each recess,respectively, for interconnecting the slab and the beam, said fasteningmeans including an angle member having a first section rigidly securedto the slab and a second section integral with the first section andextending laterally therefrom, said second section being disposedsubstantially flush with said one face and having a hole therethroughalignable with said opening of the beam, an angle element having a pairof opposed sides with each side having an outer marginal edge, themarginal edges of said sides being rigidly secured to said firstsection, said sides defining a space aligned with said hole in thesecond section, each of said sides having a side marginal edge, and aplate spanning the side marginal eDges of said sides for use in clampingsaid slab to the beam when a bolt extends through the opening, the holeand the space and when a nut is threaded onto the bolt.
 8. A buildingunit comprising: a concrete slab having a pair of opposed faces and anouter periphery provided with a number of spaced recesses extending intothe slab; and fastening means in each recess respectively, said meansincluding an angle member having a first section rigidly secured to theslab and a second section provided with an opening therethrough forreceiving a fastening device, and an angle element having a pair ofsides with each side having an outermost marginal edge, the marginaledge of said sides being rigidly secured to the first section to presenta space between said sides and aligned with the opening in the secondsection whereby the slab can be coupled to a supporting framework by thedevice, the second section being adjacent to one of the faces.
 9. Abuilding unit as set forth in claim 8, wherein each side of said elementhas an end marginal edge, and including a plate for spanning said endmarginal edges and having a hole therethrough alignable with said space.10. A building unit as set forth in claim 9, wherein the end marginaledges of said element are disposed between said opposed faces.
 11. Abuilding unit as set forth in claim 8, wherein said slab has aperipheral end face adjacent to each recess, respectively, the firstsection being substantially flush with said end face.